[evolution-kolab/ek-wip-porting] CamelIMAPXExtdServer: register untagged handlers once per server instance

[Christian Hilberg <chilberg src gnome org>]

commit 6689289f1139f19c87da5787da9c947805191901
Author: Christian Hilberg <hilberg kernelconcepts de>
Date:   Mon Sep 10 10:47:47 2012 +0200

    CamelIMAPXExtdServer: register untagged handlers once per server instance
    
    * make sure we do register the untagged handler functions
      only once per CamelIMAPXServer instance
    * using a G_ONCE here would not work, since there would
      be handler registration only once per process (not
      once per server instance), which leads to arbitrary
      folders not being down-synced (since for one or the
      other server instance, there's no untagged handler
      function (metadata, ACL) registered)

 src/libekolab/camel-imapx-extd-server.c |   27 +++++++++++++++++++++------
 1 files changed, 21 insertions(+), 6 deletions(-)
---
diff --git a/src/libekolab/camel-imapx-extd-server.c b/src/libekolab/camel-imapx-extd-server.c
index 85abdde..25de9fb 100644
--- a/src/libekolab/camel-imapx-extd-server.c
+++ b/src/libekolab/camel-imapx-extd-server.c
@@ -103,20 +103,35 @@ camel_imapx_extd_server_init (CamelIMAPXServer *is,
                               GError **err)
 {
 	gpointer prev = NULL;
+	static GMutex init_lock;
+	static GHashTable *inited_tbl = NULL;
 	
 	g_assert (CAMEL_IS_IMAPX_SERVER (is));
 	(void)cancellable; /* cancellable may be NULL */
 	g_return_val_if_fail (err == NULL || *err == NULL, FALSE);
 
-	prev = imapx_extd_server_register_untagged_fn (is);
+	g_mutex_lock (&init_lock);
 
-	if (prev != NULL) {
-		g_warning ("%s()[%u] %s",
-		           __func__,
-		           __LINE__,		           
-		           _("A CamelIMAPXServer extended untagged response handler has been registered twice"));
+	if (inited_tbl == NULL) {
+		inited_tbl = g_hash_table_new_full (g_direct_hash,
+		                                    g_direct_equal,
+		                                    NULL,
+		                                    NULL);
 	}
 
+	if (g_hash_table_lookup (inited_tbl, (gpointer) is) == NULL) {	
+		prev = imapx_extd_server_register_untagged_fn (is);
+		g_hash_table_insert (inited_tbl, (gpointer) is, (gpointer) is);
+		if (prev != NULL) {
+			g_warning ("%s()[%u] %s",
+			           __func__,
+			           __LINE__,		           
+			           _("A CamelIMAPXServer extended untagged response handler has been registered twice"));
+		}
+	}
+
+	g_mutex_unlock (&init_lock);
+
 	return TRUE;
 }